US20220020984A1 - Cathode for lithium secondary battery and lithium secondary battery including the same - Google Patents
Cathode for lithium secondary battery and lithium secondary battery including the same Download PDFInfo
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- US20220020984A1 US20220020984A1 US17/377,024 US202117377024A US2022020984A1 US 20220020984 A1 US20220020984 A1 US 20220020984A1 US 202117377024 A US202117377024 A US 202117377024A US 2022020984 A1 US2022020984 A1 US 2022020984A1
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- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 81
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 81
- 239000006182 cathode active material Substances 0.000 claims abstract description 214
- 239000002245 particle Substances 0.000 claims abstract description 205
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 66
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 31
- 229910021450 lithium metal oxide Inorganic materials 0.000 claims abstract description 20
- 239000000203 mixture Substances 0.000 claims abstract description 18
- 238000009826 distribution Methods 0.000 claims abstract description 9
- 229910052751 metal Inorganic materials 0.000 claims description 28
- 239000002184 metal Substances 0.000 claims description 28
- 239000000126 substance Substances 0.000 claims description 23
- 229910017052 cobalt Inorganic materials 0.000 claims description 17
- 239000010941 cobalt Substances 0.000 claims description 17
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 17
- 229910052748 manganese Inorganic materials 0.000 claims description 16
- 150000002739 metals Chemical class 0.000 claims description 13
- 229910052782 aluminium Inorganic materials 0.000 claims description 10
- 239000011163 secondary particle Substances 0.000 claims description 10
- 229910052719 titanium Inorganic materials 0.000 claims description 8
- 229910052796 boron Inorganic materials 0.000 claims description 7
- 229910052749 magnesium Inorganic materials 0.000 claims description 7
- 229910052726 zirconium Inorganic materials 0.000 claims description 7
- 229910052804 chromium Inorganic materials 0.000 claims description 6
- 229910052750 molybdenum Inorganic materials 0.000 claims description 6
- 229910052802 copper Inorganic materials 0.000 claims description 5
- 230000001186 cumulative effect Effects 0.000 claims description 5
- 239000011164 primary particle Substances 0.000 claims description 5
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 229910052721 tungsten Inorganic materials 0.000 claims description 4
- 229910005518 NiaCobMnc Inorganic materials 0.000 claims description 3
- 229910052791 calcium Inorganic materials 0.000 claims description 3
- 229910052733 gallium Inorganic materials 0.000 claims description 3
- 229910052758 niobium Inorganic materials 0.000 claims description 3
- 229910052708 sodium Inorganic materials 0.000 claims description 3
- 229910052712 strontium Inorganic materials 0.000 claims description 3
- 229910052720 vanadium Inorganic materials 0.000 claims description 3
- 229910052727 yttrium Inorganic materials 0.000 claims description 3
- 229910052725 zinc Inorganic materials 0.000 claims description 3
- 239000010410 layer Substances 0.000 description 75
- 239000011572 manganese Substances 0.000 description 24
- 230000000052 comparative effect Effects 0.000 description 17
- 239000002243 precursor Substances 0.000 description 17
- 239000011230 binding agent Substances 0.000 description 14
- 238000000034 method Methods 0.000 description 13
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 11
- 239000003792 electrolyte Substances 0.000 description 9
- 239000006258 conductive agent Substances 0.000 description 8
- 238000000926 separation method Methods 0.000 description 8
- 239000011149 active material Substances 0.000 description 7
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- 239000010936 titanium Substances 0.000 description 6
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- 238000003860 storage Methods 0.000 description 5
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 4
- 239000005977 Ethylene Substances 0.000 description 4
- 239000006183 anode active material Substances 0.000 description 4
- 239000010949 copper Substances 0.000 description 4
- 238000007599 discharging Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 239000002002 slurry Substances 0.000 description 4
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 description 3
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 description 3
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 229920001577 copolymer Polymers 0.000 description 3
- JBTWLSYIZRCDFO-UHFFFAOYSA-N ethyl methyl carbonate Chemical compound CCOC(=O)OC JBTWLSYIZRCDFO-UHFFFAOYSA-N 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 229910003002 lithium salt Inorganic materials 0.000 description 3
- 159000000002 lithium salts Chemical class 0.000 description 3
- 238000007669 thermal treatment Methods 0.000 description 3
- DHKHKXVYLBGOIT-UHFFFAOYSA-N 1,1-Diethoxyethane Chemical compound CCOC(C)OCC DHKHKXVYLBGOIT-UHFFFAOYSA-N 0.000 description 2
- VAYTZRYEBVHVLE-UHFFFAOYSA-N 1,3-dioxol-2-one Chemical compound O=C1OC=CO1 VAYTZRYEBVHVLE-UHFFFAOYSA-N 0.000 description 2
- YEJRWHAVMIAJKC-UHFFFAOYSA-N 4-Butyrolactone Chemical compound O=C1CCCO1 YEJRWHAVMIAJKC-UHFFFAOYSA-N 0.000 description 2
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 2
- 229910001228 Li[Ni1/3Co1/3Mn1/3]O2 (NCM 111) Inorganic materials 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 230000004075 alteration Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000006256 anode slurry Substances 0.000 description 2
- 239000012298 atmosphere Substances 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 239000003013 cathode binding agent Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 229910001416 lithium ion Inorganic materials 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
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- 239000003960 organic solvent Substances 0.000 description 2
- -1 polyethylene terephthalate Polymers 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- RUOJZAUFBMNUDX-UHFFFAOYSA-N propylene carbonate Chemical compound CC1COC(=O)O1 RUOJZAUFBMNUDX-UHFFFAOYSA-N 0.000 description 2
- 239000002356 single layer Substances 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 229920003048 styrene butadiene rubber Polymers 0.000 description 2
- 239000002562 thickening agent Substances 0.000 description 2
- 229910052723 transition metal Inorganic materials 0.000 description 2
- 150000003624 transition metals Chemical class 0.000 description 2
- SJHAYVFVKRXMKG-UHFFFAOYSA-N 4-methyl-1,3,2-dioxathiolane 2-oxide Chemical compound CC1COS(=O)O1 SJHAYVFVKRXMKG-UHFFFAOYSA-N 0.000 description 1
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- BTBUEUYNUDRHOZ-UHFFFAOYSA-N Borate Chemical compound [O-]B([O-])[O-] BTBUEUYNUDRHOZ-UHFFFAOYSA-N 0.000 description 1
- XTHFKEDIFFGKHM-UHFFFAOYSA-N Dimethoxyethane Chemical compound COCCOC XTHFKEDIFFGKHM-UHFFFAOYSA-N 0.000 description 1
- 229910005143 FSO2 Inorganic materials 0.000 description 1
- 229910018276 LaSrCoO3 Inorganic materials 0.000 description 1
- 229910018281 LaSrMnO3 Inorganic materials 0.000 description 1
- 229910011715 LiNi0.80 Inorganic materials 0.000 description 1
- 229910001290 LiPF6 Inorganic materials 0.000 description 1
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000002174 Styrene-butadiene Substances 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Chemical class 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- IAQRGUVFOMOMEM-UHFFFAOYSA-N butene Natural products CC=CC IAQRGUVFOMOMEM-UHFFFAOYSA-N 0.000 description 1
- OJIJEKBXJYRIBZ-UHFFFAOYSA-N cadmium nickel Chemical compound [Ni].[Cd] OJIJEKBXJYRIBZ-UHFFFAOYSA-N 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 239000003575 carbonaceous material Substances 0.000 description 1
- 239000001768 carboxy methyl cellulose Substances 0.000 description 1
- 235000010948 carboxy methyl cellulose Nutrition 0.000 description 1
- 239000008112 carboxymethyl-cellulose Substances 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910001914 chlorine tetroxide Inorganic materials 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
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- 238000000576 coating method Methods 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 description 1
- VUPKGFBOKBGHFZ-UHFFFAOYSA-N dipropyl carbonate Chemical compound CCCOC(=O)OCCC VUPKGFBOKBGHFZ-UHFFFAOYSA-N 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
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- 239000000835 fiber Substances 0.000 description 1
- 230000002431 foraging effect Effects 0.000 description 1
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- 229910021389 graphene Inorganic materials 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 235000015110 jellies Nutrition 0.000 description 1
- 239000008274 jelly Substances 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- FUJCRWPEOMXPAD-UHFFFAOYSA-N lithium oxide Chemical compound [Li+].[Li+].[O-2] FUJCRWPEOMXPAD-UHFFFAOYSA-N 0.000 description 1
- 229910001947 lithium oxide Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- KKQAVHGECIBFRQ-UHFFFAOYSA-N methyl propyl carbonate Chemical compound CCCOC(=O)OC KKQAVHGECIBFRQ-UHFFFAOYSA-N 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 229910021382 natural graphite Inorganic materials 0.000 description 1
- 239000004745 nonwoven fabric Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- VLTRZXGMWDSKGL-UHFFFAOYSA-M perchlorate Chemical compound [O-]Cl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-M 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 1
- 229920005569 poly(vinylidene fluoride-co-hexafluoropropylene) Polymers 0.000 description 1
- 229920002239 polyacrylonitrile Polymers 0.000 description 1
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- 229910001220 stainless steel Inorganic materials 0.000 description 1
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- HXJUTPCZVOIRIF-UHFFFAOYSA-N sulfolane Chemical compound O=S1(=O)CCCC1 HXJUTPCZVOIRIF-UHFFFAOYSA-N 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 229910052718 tin Inorganic materials 0.000 description 1
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 1
- 229910001887 tin oxide Inorganic materials 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 150000003623 transition metal compounds Chemical class 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Images
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/364—Composites as mixtures
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
- H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Definitions
- the present invention relates to a cathode for a lithium secondary battery and a lithium secondary battery including the same. More particularly, the present invention relates to a cathode for a lithium secondary battery including a lithium metal oxide-based cathode active material, and a lithium secondary battery including the same.
- a secondary battery which can be charged and discharged repeatedly has been widely employed as a power source of a mobile electronic device such as a camcorder, a mobile phone, a laptop computer, etc., according to developments of information and display technologies. Recently, a battery pack including the secondary battery is being developed and applied as a power source of an eco-friendly vehicle such as a hybrid automobile.
- the secondary battery includes, e.g., a lithium secondary battery, a nickel-cadmium battery, a nickel-hydrogen battery, etc.
- the lithium secondary battery is highlighted due to high operational voltage and energy density per unit weight, a high charging rate, a compact dimension, etc.
- the lithium secondary battery may include an electrode assembly including a cathode, an anode and a separation layer (separator), and an electrolyte immersing the electrode assembly.
- the lithium secondary battery may further include an outer case having, e.g., a pouch shape.
- a lithium metal oxide may be used as a cathode active material of the lithium secondary battery preferably having high capacity, power and life-span.
- a pressing process is performed to obtain a high energy density as an application of the lithium secondary battery becomes expanded, cracks may be generated in the cathode active material.
- a side reaction with the electrolyte may be caused to generate a gas in the battery and to degrade a long term-life span and high temperature storage properties.
- a thermal stability for preventing a short-circuit and an ignition when a penetration by an external object occurs may be required in the lithium secondary battery or the cathode active material.
- the cathode active material satisfying the above-mentioned properties may not be easily obtained.
- Korean Publication of Patent Application No. 10-2017-0093085 discloses a cathode active material including a transition metal compound and an ion adsorbing binder, which may not provide sufficient life-span and stability.
- a cathode for a lithium secondary battery having improved operational stability and reliability.
- a lithium secondary battery including the cathode.
- a cathode for a lithium secondary battery includes a cathode current collector, and a first cathode active material layer including a first cathode active material particle and a second cathode active material layer including a second cathode active material particle.
- the first cathode active material layer and the second cathode active material layer are sequentially stacked from the cathode current collector.
- the first cathode active material particle and the second cathode active material particle have different compositions or particle structures from each other, and the first cathode active material particle and the second cathode active material particle include lithium metal oxides containing nickel.
- the second cathode active material particle has a single particle shape and has a particle size distribution satisfying Equation 1.
- D 90 and D 10 represent particle size values corresponding to 90% and 10%, respectively, with respect to a maximum particle size in a volume-based cumulative particle size distribution.
- the first cathode active material particle may have a secondary particle structure in which primary particles are assembled.
- a molar ratio of nickel among metals except for lithium in the first cathode active material particle may be 60% or more.
- the first cathode active material particle may include a lithium metal oxide represented by Chemical Formula 1.
- M1 and M2 may each include at least one element selected from the group consisting of Co, Mn, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga and B, and 0 ⁇ x ⁇ 1.2, 2 ⁇ y ⁇ 2.02, 0.6 ⁇ a ⁇ 0.95, and 0.05 ⁇ b+c ⁇ 0.4.
- the first cathode active material particle may include a concentration gradient region between a central portion and a surface, and a concentration gradient of at least one metal may be formed in the concentration gradient region.
- the second cathode active material particle may further include cobalt, and a molar ratio of cobalt among metals except for lithium in the second cathode active material particle may be 15% or less.
- a molar ratio of nickel among metals except for lithium in the second cathode active material particle may be 50% or more.
- elements of a lithium metal oxide included in the second cathode active material particle may have constant concentrations from a central portion to a surface.
- an average particle diameter of the second cathode active material particle may be in a range from 3 ⁇ m to 6 ⁇ m.
- the second cathode active material particle may include a lithium metal oxide represented by Chemical Formula 2.
- M4 may include at least one element selected from the group consisting of Ti, Zr, Al, Mg, Si, B and Cr
- M5 may include at least one element selected from the group consisting of Sr, Y, W and Mo, and 0 ⁇ x ⁇ 1.5, 2 ⁇ y ⁇ 2.02, 0.50 ⁇ a ⁇ 0.75, 0.05 ⁇ b ⁇ 0.15, 0.20 ⁇ c ⁇ 0.30, 0 ⁇ d ⁇ 0.03, 0 ⁇ e ⁇ 0.03 and 0.98 ⁇ a+b+c ⁇ 1.03.
- a crystallite size of the second cathode active material particle may be in a range from 200 nm to 600 nm.
- a weight ratio of the second cathode active material particle and the first cathode active material particle included in the cathode may be 1:9 to 6:4.
- a nickel content in the second cathode active material particle may be smaller than that in the first cathode active material particle.
- an average diameter of the second cathode active material particle may be smaller than that of the first cathode active material particle.
- a lithium secondary battery including the cathode for a lithium secondary battery as described above, and an anode facing the cathode is provided.
- the lithium secondary battery according to exemplary embodiments as described above may include a cathode active material layer having a multi-layered structure.
- the cathode active material layer may include a first cathode active material layer having a cathode active material particle of a multi-particle structure, and a second cathode active material layer having a cathode active material particle of a single particle shape.
- cracks of a cathode active material caused during a pressing process may be prevented so that mechanical and electrical stability of the cathode may be enhanced while achieving a high energy density of the lithium secondary battery.
- a 90% particle size with respect to a maximum particle size in a cumulative particle size distribution relative to a 10% particle size with respect to a maximum particle size in a cumulative particle size distribution may be 4 or less.
- a high-capacity battery may be obtained while improving a conductivity and life-span of the battery.
- FIG. 1 is a schematic cross-sectional view illustrating a cathode for a lithium secondary battery in accordance with exemplary embodiments.
- FIGS. 2 and 3 are a schematic top planar view and a schematic cross-sectional view illustrating a lithium secondary battery in accordance with exemplary embodiments.
- FIG. 4 is a graph showing gas generations from lithium secondary batteries of Examples and Comparative Examples in a high temperature storage.
- a cathode for a lithium secondary battery having a multi-layered structure that includes a first active material layer and a second active material layer which include different cathode active material particles is provided.
- a lithium secondary battery including the cathode is also provided.
- first and second are used herein not to limit the number or the order of elements or objects, but to relatively designate different elements.
- FIG. 1 is a schematic cross-sectional view illustrating a cathode for a lithium secondary battery in accordance with exemplary embodiments.
- a cathode 100 may include a cathode active material layer 110 formed on at least one surface of a cathode current collector 105 .
- the cathode material layer 110 may be formed on both surfaces (e.g., upper and lower surfaces) of the cathode current collector 105 .
- the cathode current collector 105 may include, e.g., stainless steel, nickel, aluminum, titanium, copper or an alloy thereof, and may preferably aluminum or an aluminum alloy.
- the cathode active material layer 110 may include a first cathode active material layer 112 and a second cathode active material layer 114 . Accordingly, the cathode active material layer 110 may have a multi-layered structure (e.g., a double-layered structure) in which a plurality of cathode active material layers may be stacked.
- a multi-layered structure e.g., a double-layered structure
- the first cathode active material layer 112 may be formed on a surface of the cathode current collector 105 .
- the first cathode active material layer 112 may be formed on each of the upper and lower surfaces of the cathode current collector 105 . As illustrated in FIG. 1 , the first cathode active material layer 112 may directly contact the surface of the cathode current collector 105 .
- the first cathode active material layer 112 may include first cathode active material particles.
- the first cathode active material particle may include a lithium metal oxide containing nickel and another transition metal.
- nickel in the first cathode active material particle, nickel may be included in the highest content (molar ratio) among metals other than lithium, and the content of nickel among the metals except lithium may be about 60 mol % or more, preferably 80 mol % or more. In this case, a lithium secondary battery having a high energy density may be obtained.
- the nickel content (or molar ratio) of the first cathode active material particle may be greater than that of a second cathode active material particle as will be described later.
- the first cathode active material particle may include a lithium metal oxide represented by the following Chemical Formula 1.
- M1 and M2 may be at least one element selected from the group consisting of Co, Mn, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga and B.
- M1 and M2 in Chemical Formula 1 may be cobalt (Co) and manganese (Mn), respectively.
- nickel may serve as a metal related to a power and/or a capacity of the lithium secondary battery.
- the lithium metal oxide having a nickel content of 0.8 or more may be employed as the first cathode active material particle, and the first cathode active material layer 112 may be formed to be in contact with the cathode current collector 105 , so that high power and high capacity may be effectively obtained from the cathode 100 .
- manganese (Mn) may serve as a metal related to mechanical and electrical stability of the lithium secondary battery.
- cobalt (Co) may be a metal related to a conductivity or a resistance of the lithium secondary battery.
- 0.7 ⁇ a ⁇ 0.9 and 0.1 ⁇ b+c ⁇ 0.3 in consideration of achieving high power and high capacity from the first cathode active material layer 112 .
- the concentration ratio (or molar ratio) of nickel:cobalt:manganese in the first cathode active material particle may be adjusted to about 8:1:1.
- the conductivity and life-span property may be maintained by including cobalt and manganese while increasing capacity and power by employing nickel in a molar ratio of about 0.8.
- the first cathode active material particle may have a concentration gradient.
- the first cathode active material particle may include the lithium metal oxide in which a concentration gradient of at least one metal is formed.
- the first cathode active material particle may include a concentration gradient region between a central portion and a surface.
- the first cathode active material particle may include a core region and a shell region, and the concentration gradient region may be formed between the core region and the shell region.
- the core region and the shell region may each have a uniform or fixed concentration.
- the concentration gradient region may be formed at the central portion. In an embodiment, the concentration gradient region may be formed at the shell region or a surface portion.
- the first cathode active material particle may include the lithium metal oxide having a continuous concentration gradient from a center of the particle to a surface of the particle.
- the first cathode active material particle may have a full concentration gradient (FCG) structure having a substantially entire concentration gradient throughout the particle.
- continuous concentration gradient used herein may indicate a concentration profile which may be changed with a uniform trend or tendency between the center and the surface.
- the uniform trend may include an increasing trend or a decreasing trend.
- central portion used herein may include a central point of the active material particle and may also include a region within a predetermined radius from the central point.
- central portion may encompass a region within a radius of about 0.1 ⁇ m from the central point of the active material particle.
- surface may include an outermost surface of the active material particle, and may also include a predetermined thickness from the outermost surface.
- surface or surface portion may include a region within a thickness of about 0.1 ⁇ m from the outermost surface of the active material particle.
- the continuous concentration gradient may include a linear concentration profile or a curved concentration profile.
- the concentration may change in a uniform trend without any inflection point.
- At least one metal except for lithium included in the first cathode active material particle may have an increasing continuous concentration gradient, and at least one metal except for lithium included in the first cathode active material particle may have a decreasing continuous concentration gradient. In an embodiment, at least one metal included in the first cathode active material particle except for lithium may have a substantially constant concentration from the central portion to the surface.
- the concentration (or the molar ratio) of Ni may be continuously decreased from the central portion to the surface or in the concentration gradient region.
- a concentration of Ni may be decreased in a direction from the central portion to the surface within a range between about 0.95 and about 0.6.
- a concentration of manganese may increase from the center to the surface or in the concentration gradient region.
- a content of manganese may increase at a region adjacent to the surface, so that defects such as an ignition and short-circuit caused by a penetration through the surface of the first cathode active material particle may be prevented or reduced, and a life-span of the lithium secondary electricity may be increased.
- the content of manganese may be maintained substantially constant throughout an entire region of the first cathode active material particle.
- a concentration of cobalt may increase along a direction toward the surface in the concentration gradient region.
- the content of cobalt may be maintained substantially constant throughout an entire region of the first cathode active material particle.
- nickel, cobalt and manganese included in the first cathode active material particle may have a substantially constant concentration from the center to the surface, and the first cathode active material particle is not necessarily limited to a particle having the above-described concentration gradient region.
- the first cathode active material particle may have a multi-particle structure.
- multi-particle may refer to a secondary particle structure or a secondary particle shape formed by aggregation or assembly of a plurality of primary particles.
- the first cathode active material particle may be formed by a co-precipitation method of metal precursors.
- a metal precursor solution may include precursors of metals that may be included in the cathode active material.
- the metal precursors may include halides, hydroxides, acid salts, etc., of the metals.
- the metal precursors may include a lithium precursor (e.g., lithium oxide, lithium hydroxide, etc.), a nickel precursor, a manganese precursor and a cobalt precursor.
- a lithium precursor e.g., lithium oxide, lithium hydroxide, etc.
- nickel precursor e.g., nickel precursor
- manganese precursor e.g., manganese precursor
- the first cathode active material particle may be prepared by a solid phase mixing/reaction, and a method of preparing the first cathode active material particle is not be limited to the solution-based process.
- the first cathode active material particle may be mixed and stirred together with a binder, a conductive agent and/or a dispersive additive in a solvent to form a slurry.
- the slurry may be coated on the cathode current collector 105 , and dried and pressed to obtain the first cathode active material layer 112 .
- the binder may include an organic based binder such as a polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride (PVDF), polyacrylonitrile, polymethylmethacrylate, etc., or an aqueous based binder such as styrene-butadiene rubber (SBR) that may be used with a thickener such as carboxymethyl cellulose (CMC).
- organic based binder such as a polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride (PVDF), polyacrylonitrile, polymethylmethacrylate, etc.
- an aqueous based binder such as styrene-butadiene rubber (SBR) that may be used with a thickener such as carboxymethyl cellulose (CMC).
- SBR
- a PVDF-based binder may be used as a cathode binder.
- an amount of the binder for forming the first cathode active material layer 112 , and an amount of the first cathode active material particles may be relatively increased.
- capacity and power output of the lithium secondary battery may be further improved.
- a PVDF-based binder may be used as a cathode binder.
- an amount of the binder for forming the first cathode active material layer 112 , and an amount of the first cathode active material particles may be relatively increased.
- capacity and power of the lithium secondary battery may be further improved.
- the conductive agent may be added to facilitate electron mobility between the active material particles.
- the conductive agent may include a carbon-based material such as graphite, carbon black, graphene, carbon nanotube, etc., and/or a metal-based material such as tin, tin oxide, titanium oxide, a perovskite material such as LaSrCoO 3 or LaSrMnO 3 , etc.
- the second cathode active material layer 114 may be formed on the first cathode active material layer 112 . As illustrated in FIG. 1 , the second cathode active material layer 114 may be directly formed on an upper surface of the first cathode active material layer 112 , and may serve as a coating layer of the cathode 100 .
- the second cathode active material layer 114 may include a second cathode active material particle.
- the second cathode active material particle may include a lithium metal oxide containing nickel, cobalt and other transition metals.
- a content (or molar ratio) of cobalt in the second cathode active material particle may be 15% or less. In this case, improved conductivity and low resistance may be achieved while realizing high power/capacity of the lithium secondary battery.
- the second cathode active material particle may have a single particle shape or a single particle structure.
- the term “single particle shape” herein may be used to exclude a secondary particle structure in which a plurality of primary particles mat be agglomerated or combined with each other.
- the second cathode active material particle may have a structure in which a plurality of primary particles are integrally merged to be converted into a substantially single particle.
- the single particle shape may include a monolithic shape in which several (e.g., 2 to 10 ) independent particles are adjacent or attached to each other.
- the second cathode active material particle may have a substantially constant or fixed concentration throughout an entire region of the particle.
- concentrations of metals except for lithium may be substantially uniform or constant from a central portion of the particle to a surface of the particle in the second cathode active material particle.
- the second cathode active material particle may include nickel (Ni), cobalt (Co) and manganese (Mn). As described above, concentrations or molar ratios of Ni, Co and Mn may be substantially uniform or constant throughout the entire region of the second cathode active material particle.
- a concentration of nickel in the second cathode active material particle may be less than a concentration of nickel in the first cathode active material particle.
- the concentration of nickel in the second cathode active material particle may be fixed to be less than the concentration of nickel at the surface of the first cathode active material particle.
- a molar ratio of Ni among metals except for lithium in the second cathode active material particle may be 50% or more, preferably 60% or more. Within this range, sufficient thermal and penetration stability may be obtained from the second cathode active material layer 114 without degrading capacity/power output of the cathode 100 .
- the second cathode active material particle may include a lithium metal oxide represented by the following Chemical Formula 2.
- M4 may include at least one element selected from Ti, Zr, Al, Mg, Si, B or Cr.
- M5 may include at least one element selected from Sr, Y, W or Mo.
- an amount of Ni may be largest of those of the metals except for lithium in the second cathode active material particle in consideration of capacity and stability of the lithium secondary battery.
- the concentrations may be decreased in a sequential order of Ni, Mn and Co.
- the concentration ratio of Ni:Co:Mn in the second cathode active material particle may be substantially about 65:15:20.
- the second cathode active material particle may be prepared by a solid-state thermal treatment of the metal precursors.
- a lithium precursor, the nickel precursor, the manganese precursor and the cobalt precursor may be mixed according to the composition of the Chemical Formula 2 above to form a precursor powder.
- the precursor powder may be thermally treated in a furnace at, e.g., a temperature from about 700° C. to about 1200° C., and the precursors may be merged or fused into a substantially single particle shape to obtain the second cathode active material particle having a single particle shape.
- the thermal treatment may be performed under an air atmosphere or an oxygen atmosphere so that the second cathode active material particle may be formed as a lithium metal oxide particle.
- the thermal treatment may be performed at a temperature from about 800° C. to about 1,000° C.
- the second cathode active material may be mixed and stirred together with a binder, a conductive agent and/or a dispersive additive in a solvent to form a slurry.
- the slurry may be coated on the first cathode active material layer 112 , and dried and pressed to obtain the second cathode active material layer 114 .
- the binder and the conductive agent substantially the same as or similar to those used in the first cathode active material layer 112 may be also used.
- a weight ratio of the second cathode active material particle and the first cathode active material particle included in the cathode active material layer 110 may be from 1:9 to 6:4.
- the weight ratio of the first cathode active material particles and the second cathode active material particles having different compositions or molar ratios from each other may be controlled to implement enhanced mechanical property and high energy while using the multi-layered structure.
- the first cathode active material layer 112 contacting the cathode current collector 105 may include the lithium metal oxide having a higher nickel amount than that of the second cathode active material particle in the second cathode active material layer 114 .
- high capacity/power may be effectively achieved from a current through the cathode current collector 105 .
- the second cathode active material layer 114 that may be exposed at an outer surface of the cathode 100 may include the second cathode active material particle having a relatively reduced nickel amount so that thermal stability and life-span stability may be enhanced.
- the second cathode active material layer 114 may include the second cathode active material particle having a structure of the single particle shape to suppress generation of cracks during a pressing process.
- the second cathode active material layer 114 may substantially serve as a cathode coating layer improving the mechanical property.
- an average diameter of the second cathode active material particle (D 50 ) may be in a range from 3 ⁇ m to 6 ⁇ m, and a particle size distribution of the second cathode active material particles may satisfy Equation 1 below.
- D 90 and D 10 represent particle size values corresponding to 90% and 10%, respectively, with respect to a maximum particle size in a volume-based cumulative particle size distribution.
- a particle deformation in the second positive electrode active material layer may be suppressed to achieve the lithium secondary battery having a high energy density while implementing a long-term storage property.
- a diameter (e.g., D 50 ) of the second cathode active material particle may be smaller than that of the first cathode active material particle. Accordingly, a packing property in the second cathode active material layer 114 may be increased, and propagation of heat or crack when being penetrated or pressed may be more effectively suppressed or reduced.
- the second cathode active material particle may have a crystallite size from 200 nm to 600 nm.
- the crystallite size may be measured based on a 104 peak according to an X-ray diffraction pattern analysis (XRD analysis).
- XRD analysis X-ray diffraction pattern analysis
- the crystallite size may be estimated using a peak broadening of XRD data, and the crystallite size may be quantitatively calculated using a Scherrer equation.
- the first cathode active material particle and/or the second cathode active material particle may further include a coating layer on a surface thereof.
- the coating layer may include Al, Ti, Ba, Zr, Si, B, Mg, P, W, an alloy thereof or on oxide thereof. These may be used alone or in a combination thereof.
- the first cathode active material particle may be passivated by the coating layer so that penetration stability and life-span of the battery may be further improved.
- the elements, the alloy or the oxide of the coating layer may be inserted in the cathode active material particle as dopants.
- a thickness of the second cathode active material layer 114 may be less than that of the first cathode active material layer 112 . Accordingly, the second cathode active material layer 114 may serve as a coating layer providing a penetration barrier, and the first cathode active material layer 112 may serve as an active layer providing power/capacity.
- the thickness of the first cathode active material layer 112 may be in a range from about 50 ⁇ m to about 200 ⁇ m.
- the thickness of the second cathode active material layer 114 may be in a range from about 10 ⁇ m to about 100 ⁇ m.
- FIGS. 2 and 3 are a top planar view and a cross-sectional view, respectively, schematically illustrating a lithium secondary battery in accordance with exemplary embodiments. Specifically, FIG. 3 is a cross-sectional view taken along a line I-I′ of FIG. 2 in a thickness direction of the lithium secondary battery.
- a lithium secondary battery 200 may include an electrode assembly 150 housed in a case 160 .
- the electrode assembly 150 may include the cathode 100 , an anode 130 and a separation layer 140 repeatedly stacked as illustrated in FIG. 3 .
- the cathode 100 may include the cathode active material layer 110 coated on the cathode current collector 105 .
- the cathode active material layer 110 may include a multi-layered structure including the first cathode active material layer 112 and the second cathode active material layer 114 as described with reference to FIG. 1 .
- the anode 130 may include an anode current collector 125 and an anode active material layer 120 formed by coating an anode active material on the anode current collector 125 .
- the anode active material commonly used in the related art may be used without a specific limitation.
- the separation layer 140 may be interposed between the cathode 100 and the anode 130 .
- the separation layer 140 may include a porous polymer film prepared from, e.g., a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene/butene copolymer, an ethylene/hexene copolymer, an ethylene/methacrylate copolymer, or the like.
- the separation layer 140 may be also formed from a non-woven fabric including a glass fiber with a high melting point, a polyethylene terephthalate fiber, or the like.
- an area and/or a volume of the anode 130 may be greater than that of the cathode 100 .
- lithium ions generated from the cathode 100 may be easily transferred to the anode 130 without loss by, e.g., precipitation or sedimentation. Therefore, the enhancement of power and stability by the combination of the first and second cathode active material layers 112 and 114 may be effectively implemented.
- an electrode cell may be defined by the cathode 100 , the anode 130 and the separation layer 140 , and a plurality of the electrode cells may be stacked to form an electrode assembly 150 having, e.g., a jelly roll shape.
- the electrode assembly 150 may be formed by winding, laminating or folding of the separation layer 140 .
- the electrode assembly 150 may be accommodated in an outer case 160 together with an electrolyte to form the lithium secondary battery.
- the electrolyte may include a non-aqueous electrolyte solution.
- the non-aqueous electrolyte solution may include a lithium salt and an organic solvent.
- the lithium salt may be represented by Li + X ⁇
- an anion of the lithium salt X ⁇ may include, e.g., F ⁇ , Cl ⁇ , Br ⁇ , I ⁇ , NO 3 ⁇ , N(CN) 2 ⁇ , BF 4 ⁇ , ClO 4 ⁇ , PF 6 ⁇ , (CF 3 ) 2 PF 4 ⁇ , (CF 3 ) 3 PF 3 ⁇ , (CF 3 ) 4 PF 2 ⁇ , (CF 3 ) 5 PF ⁇ , (CF 3 ) 6 P ⁇ , CF 3 SO 3 ⁇ , CF 3 CF 2 SO 3 ⁇ , (CF 3 SO 2 ) 2 N ⁇ , (FSO 2 ) 2 N ⁇ , CF 3 CF 2 (CF 3 ) 2 CO ⁇ , (CF 3 SO 2 ) 2 CH ⁇ , (
- the organic solvent may include propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), methylpropyl carbonate, dipropyl carbonate, dimethyl sulfoxide, acetonitrile, dimethoxy ethane, diethoxy ethane, vinylene carbonate, sulfolane, gamma-butyrolactone, propylene sulfite, tetrahydrofuran, etc. These may be used alone or in a combination thereof.
- an electrode tab (a cathode tab and an anode tab) may be formed from each of the cathode current collector 105 and the anode current collector 125 to extend to one end of the case 160 .
- the electrode tabs may be welded together with the one end of the case 160 to form an electrode lead (a cathode lead 107 and an anode lead 127 ) exposed at an outside of the case 160 .
- FIG. 2 illustrates that the cathode lead 107 and the anode lead 127 protrude from an upper side of the case 160 in a planar view.
- positions of the electrode leads are not specifically limited.
- the electrode leads may protrude from at least one of lateral sides of the case 160 , or may protrude from a lower side of the case 160 .
- the cathode lead 107 and the anode lead 127 may protrude from different sides of the case 160 .
- the lithium secondary battery may be fabricated into a cylindrical shape using a can, a prismatic shape, a pouch shape, a coin shape, etc.
- a first cathode active material particle having a secondary particle structure and a composition of LiNi 0.80 Co 0.12 Mn 0.08 O 2 was prepared.
- a first cathode mixture was prepared by mixing the first cathode active material particle, Denka Black as a conductive agent and PVDF as a binder in a mass ratio of 92:5:3, respectively.
- a second cathode mixture was prepared by mixing the second cathode active material particle, Denka Black as a conductive agent and PVDF as a binder in a mass ratio of 92:5:3, respectively.
- a mass ratio of the first cathode active material particle relative to the second cathode active material particle included in the first cathode mixture and the second cathode mixture was 8:2.
- the first cathode mixture was coated on an aluminum current collector, and the second cathode mixture was coated thereon, and then dried and pressed to form a cathode.
- An electrode density of the cathode was 3.7 g/cc.
- An anode slurry was prepared by mixing 93 wt % of a natural graphite as an anode active material, 5 wt % of a flake type conductive agent KS6, 1 wt % of SBR as a binder, and 1 wt % of CMC as a thickener. The anode slurry was coated, dried and pressed on a copper substrate to form an anode.
- the cathode and the anode obtained as described above were notched with a proper size and stacked, and a separator (polyethylene, thickness: 25 ⁇ m) was interposed between the cathode and the anode to form an electrode cell.
- a separator polyethylene, thickness: 25 ⁇ m
- Each tab portion of the cathode and the anode was welded.
- the welded cathode/separator/anode assembly was inserted in a pouch, and three sides of the pouch (e.g., except for an electrolyte injection side) were sealed.
- the tab portions were also included in sealed portions.
- An electrolyte was injected through the electrolyte injection side, and then the electrolyte injection side was also sealed. Subsequently, the above structure was impregnated for more than 12 hours.
- the electrolyte was prepared by dissolving 1M LiPF 6 in a mixed solvent of EC/EMC/DEC (25/45/30; volume ratio), and then 1 wt % of vinylene carbonate, 0.5 wt % of 1,3-propensultone (PRS), and 0.5 wt % of lithium bis(oxalato) borate (LiBOB) were added.
- pre-charging was performed for 36 minutes at a current (5 A) corresponding to 0.25 C.
- degassing was performed, and charge and discharge for aging were performed (charging condition CC-CV 0.2 C 4.2V 0.05 C CUT-OFF, discharging condition CC 0.2 C 2.5V CUT-OFF) after more than 24 hours.
- standard charging and discharging was performed (charging condition CC-CV 0.5 C 4.2V 0.05 C CUT-OFF, discharging condition CC 0.5 C 2.5V CUT-OFF).
- a lithium secondary battery was fabricated by the same method as that in Example 1, except that the first cathode active material particle and the second cathode active material particle were mixed to form a single cathode mixture, and then a cathode active material layer was formed as a single layer.
- a lithium secondary battery was fabricated by the same method as that in Example 1, except that a particle having a secondary particle structure and a composition of LiNi 0.65 Co 0.15 Mn 0.20 O 2 was used as the second cathode active material particle.
- a lithium secondary battery was fabricated by the same method as that in Example 1, except that the secondary particle of Comparative Example 2 was used as the second cathode active material particle, and the first cathode active material particle and the second cathode active material particle were mixed to form a single cathode mixture, and then a cathode active material layer was formed as a single layer.
- a lithium secondary battery was fabricated by the same method as that in Example 1, except that LiNi 1/3 Co 1/3 Mn 1/3 O 2 (single particle shape NCM111) having a single particle shape was used as the second cathode active material particle.
- the secondary battery of Comparative Example 5 having different metal ratio of the second cathode active material particle provided life-span and storage properties at high temperature less than those of Examples.
Abstract
Description
- This application claims priority to Korean Patent Application No. 10-2020-0089847 filed on Jul. 20, 2020 in the Korean Intellectual Property Office (KIPO), the entire disclosure of which is incorporated by reference herein.
- The present invention relates to a cathode for a lithium secondary battery and a lithium secondary battery including the same. More particularly, the present invention relates to a cathode for a lithium secondary battery including a lithium metal oxide-based cathode active material, and a lithium secondary battery including the same.
- A secondary battery which can be charged and discharged repeatedly has been widely employed as a power source of a mobile electronic device such as a camcorder, a mobile phone, a laptop computer, etc., according to developments of information and display technologies. Recently, a battery pack including the secondary battery is being developed and applied as a power source of an eco-friendly vehicle such as a hybrid automobile.
- The secondary battery includes, e.g., a lithium secondary battery, a nickel-cadmium battery, a nickel-hydrogen battery, etc. The lithium secondary battery is highlighted due to high operational voltage and energy density per unit weight, a high charging rate, a compact dimension, etc.
- For example, the lithium secondary battery may include an electrode assembly including a cathode, an anode and a separation layer (separator), and an electrolyte immersing the electrode assembly. The lithium secondary battery may further include an outer case having, e.g., a pouch shape.
- A lithium metal oxide may be used as a cathode active material of the lithium secondary battery preferably having high capacity, power and life-span. However, when a pressing process is performed to obtain a high energy density as an application of the lithium secondary battery becomes expanded, cracks may be generated in the cathode active material. In this case, a side reaction with the electrolyte may be caused to generate a gas in the battery and to degrade a long term-life span and high temperature storage properties. Further, a thermal stability for preventing a short-circuit and an ignition when a penetration by an external object occurs may be required in the lithium secondary battery or the cathode active material.
- However, the cathode active material satisfying the above-mentioned properties may not be easily obtained. For example, Korean Publication of Patent Application No. 10-2017-0093085 discloses a cathode active material including a transition metal compound and an ion adsorbing binder, which may not provide sufficient life-span and stability.
- According to an aspect of the present invention, there is provided a cathode for a lithium secondary battery having improved operational stability and reliability.
- According to exemplary embodiments, there is provided a lithium secondary battery including the cathode.
- According to exemplary embodiments, a cathode for a lithium secondary battery includes a cathode current collector, and a first cathode active material layer including a first cathode active material particle and a second cathode active material layer including a second cathode active material particle. The first cathode active material layer and the second cathode active material layer are sequentially stacked from the cathode current collector. The first cathode active material particle and the second cathode active material particle have different compositions or particle structures from each other, and the first cathode active material particle and the second cathode active material particle include lithium metal oxides containing nickel. The second cathode active material particle has a single particle shape and has a particle size
distribution satisfying Equation 1. -
1≤D 90 /D 10≤4 [Equation 1] - In
Equation 1, D90 and D10 represent particle size values corresponding to 90% and 10%, respectively, with respect to a maximum particle size in a volume-based cumulative particle size distribution. - In some embodiments, the first cathode active material particle may have a secondary particle structure in which primary particles are assembled.
- In some embodiments, a molar ratio of nickel among metals except for lithium in the first cathode active material particle may be 60% or more.
- In some embodiments, the first cathode active material particle may include a lithium metal oxide represented by Chemical Formula 1.
-
LixNiaM1bM2cOy [Chemical Formula 1] - In
Chemical Formula 1, M1 and M2 may each include at least one element selected from the group consisting of Co, Mn, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga and B, and 0<x≤1.2, 2≤y≤2.02, 0.6≤a≤0.95, and 0.05≤b+c≤0.4. - In some embodiments, the first cathode active material particle may include a concentration gradient region between a central portion and a surface, and a concentration gradient of at least one metal may be formed in the concentration gradient region.
- In some embodiments, the second cathode active material particle may further include cobalt, and a molar ratio of cobalt among metals except for lithium in the second cathode active material particle may be 15% or less.
- In some embodiments, a molar ratio of nickel among metals except for lithium in the second cathode active material particle may be 50% or more.
- In some embodiments, elements of a lithium metal oxide included in the second cathode active material particle may have constant concentrations from a central portion to a surface.
- In some embodiments, an average particle diameter of the second cathode active material particle may be in a range from 3 μm to 6 μm.
- In some embodiments, the second cathode active material particle may include a lithium metal oxide represented by Chemical Formula 2.
-
LixNiaCobMncM4dM5eOy [Chemical Formula 2] - In
Chemical Formula 2, M4 may include at least one element selected from the group consisting of Ti, Zr, Al, Mg, Si, B and Cr, M5 may include at least one element selected from the group consisting of Sr, Y, W and Mo, and 0<x<1.5, 2≤y≤2.02, 0.50≤a≤0.75, 0.05≤b≤0.15, 0.20≤c≤0.30, 0≤d≤0.03, 0≤e≤0.03 and 0.98≤a+b+c≤1.03. - In some embodiments, a crystallite size of the second cathode active material particle may be in a range from 200 nm to 600 nm.
- In some embodiments, a weight ratio of the second cathode active material particle and the first cathode active material particle included in the cathode may be 1:9 to 6:4.
- In some embodiments, a nickel content in the second cathode active material particle may be smaller than that in the first cathode active material particle.
- In some embodiments, an average diameter of the second cathode active material particle may be smaller than that of the first cathode active material particle.
- According to exemplary embodiments, a lithium secondary battery including the cathode for a lithium secondary battery as described above, and an anode facing the cathode is provided.
- The lithium secondary battery according to exemplary embodiments as described above may include a cathode active material layer having a multi-layered structure. The cathode active material layer may include a first cathode active material layer having a cathode active material particle of a multi-particle structure, and a second cathode active material layer having a cathode active material particle of a single particle shape.
- In this case, cracks of a cathode active material caused during a pressing process may be prevented so that mechanical and electrical stability of the cathode may be enhanced while achieving a high energy density of the lithium secondary battery.
- In exemplary embodiments, a 90% particle size with respect to a maximum particle size in a cumulative particle size distribution relative to a 10% particle size with respect to a maximum particle size in a cumulative particle size distribution may be 4 or less. In this case, a high-capacity battery may be obtained while improving a conductivity and life-span of the battery.
-
FIG. 1 is a schematic cross-sectional view illustrating a cathode for a lithium secondary battery in accordance with exemplary embodiments. -
FIGS. 2 and 3 are a schematic top planar view and a schematic cross-sectional view illustrating a lithium secondary battery in accordance with exemplary embodiments. -
FIG. 4 is a graph showing gas generations from lithium secondary batteries of Examples and Comparative Examples in a high temperature storage. - According to exemplary embodiments of the present invention, a cathode for a lithium secondary battery having a multi-layered structure that includes a first active material layer and a second active material layer which include different cathode active material particles is provided. A lithium secondary battery including the cathode is also provided.
- Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. However, those skilled in the art will appreciate that such embodiments described with reference to the accompanying drawings are provided to further understand the spirit of the present invention and do not limit subject matters to be protected as disclosed in the detailed description and appended claims.
- The terms “first” and “second” are used herein not to limit the number or the order of elements or objects, but to relatively designate different elements.
-
FIG. 1 is a schematic cross-sectional view illustrating a cathode for a lithium secondary battery in accordance with exemplary embodiments. - Referring to
FIG. 1 , acathode 100 may include a cathodeactive material layer 110 formed on at least one surface of a cathodecurrent collector 105. Thecathode material layer 110 may be formed on both surfaces (e.g., upper and lower surfaces) of the cathodecurrent collector 105. - The cathode
current collector 105 may include, e.g., stainless steel, nickel, aluminum, titanium, copper or an alloy thereof, and may preferably aluminum or an aluminum alloy. - In exemplary embodiments, the cathode
active material layer 110 may include a first cathodeactive material layer 112 and a second cathodeactive material layer 114. Accordingly, the cathodeactive material layer 110 may have a multi-layered structure (e.g., a double-layered structure) in which a plurality of cathode active material layers may be stacked. - The first cathode
active material layer 112 may be formed on a surface of the cathodecurrent collector 105. For example, the first cathodeactive material layer 112 may be formed on each of the upper and lower surfaces of the cathodecurrent collector 105. As illustrated inFIG. 1 , the first cathodeactive material layer 112 may directly contact the surface of the cathodecurrent collector 105. - The first cathode
active material layer 112 may include first cathode active material particles. The first cathode active material particle may include a lithium metal oxide containing nickel and another transition metal. In exemplary embodiments, in the first cathode active material particle, nickel may be included in the highest content (molar ratio) among metals other than lithium, and the content of nickel among the metals except lithium may be about 60 mol % or more, preferably 80 mol % or more. In this case, a lithium secondary battery having a high energy density may be obtained. - In some embodiments, the nickel content (or molar ratio) of the first cathode active material particle may be greater than that of a second cathode active material particle as will be described later.
- In some embodiments, the first cathode active material particle may include a lithium metal oxide represented by the following
Chemical Formula 1. -
LixNiaM1bM2cOy [Chemical Formula 1] - In the
Chemical Formula 1 above, M1 and M2 may be at least one element selected from the group consisting of Co, Mn, Na, Mg, Ca, Ti, V, Cr, Cu, Zn, Ge, Sr, Ag, Ba, Zr, Nb, Mo, Al, Ga and B. In theChemical Formula - In some embodiments, M1 and M2 in
Chemical Formula 1 may be cobalt (Co) and manganese (Mn), respectively. - For example, nickel may serve as a metal related to a power and/or a capacity of the lithium secondary battery. As described above, the lithium metal oxide having a nickel content of 0.8 or more may be employed as the first cathode active material particle, and the first cathode
active material layer 112 may be formed to be in contact with the cathodecurrent collector 105, so that high power and high capacity may be effectively obtained from thecathode 100. - For example, manganese (Mn) may serve as a metal related to mechanical and electrical stability of the lithium secondary battery. For example, cobalt (Co) may be a metal related to a conductivity or a resistance of the lithium secondary battery.
- In a preferable embodiment, 0.7≤a≤0.9 and 0.1≤b+c≤0.3 in consideration of achieving high power and high capacity from the first cathode
active material layer 112. - In a non-limiting embodiment, the concentration ratio (or molar ratio) of nickel:cobalt:manganese in the first cathode active material particle may be adjusted to about 8:1:1. In this case, the conductivity and life-span property may be maintained by including cobalt and manganese while increasing capacity and power by employing nickel in a molar ratio of about 0.8.
- In some embodiments, the first cathode active material particle may have a concentration gradient. For example, the first cathode active material particle may include the lithium metal oxide in which a concentration gradient of at least one metal is formed.
- In some embodiments, the first cathode active material particle may include a concentration gradient region between a central portion and a surface. For example, the first cathode active material particle may include a core region and a shell region, and the concentration gradient region may be formed between the core region and the shell region. The core region and the shell region may each have a uniform or fixed concentration.
- In an embodiment, the concentration gradient region may be formed at the central portion. In an embodiment, the concentration gradient region may be formed at the shell region or a surface portion.
- In some embodiments, the first cathode active material particle may include the lithium metal oxide having a continuous concentration gradient from a center of the particle to a surface of the particle. For example, the first cathode active material particle may have a full concentration gradient (FCG) structure having a substantially entire concentration gradient throughout the particle.
- The term “continuous concentration gradient” used herein may indicate a concentration profile which may be changed with a uniform trend or tendency between the center and the surface. The uniform trend may include an increasing trend or a decreasing trend.
- The term “central portion” used herein may include a central point of the active material particle and may also include a region within a predetermined radius from the central point. For example, “central portion” may encompass a region within a radius of about 0.1 μm from the central point of the active material particle.
- The term “surface” or “surface portion” used herein may include an outermost surface of the active material particle, and may also include a predetermined thickness from the outermost surface. For example, “surface” or “surface portion” may include a region within a thickness of about 0.1 μm from the outermost surface of the active material particle.
- In some embodiments, the continuous concentration gradient may include a linear concentration profile or a curved concentration profile. In the curved concentration profile, the concentration may change in a uniform trend without any inflection point.
- In an embodiment, at least one metal except for lithium included in the first cathode active material particle may have an increasing continuous concentration gradient, and at least one metal except for lithium included in the first cathode active material particle may have a decreasing continuous concentration gradient. In an embodiment, at least one metal included in the first cathode active material particle except for lithium may have a substantially constant concentration from the central portion to the surface.
- When the first cathode active material particle includes the concentration gradient, the concentration (or the molar ratio) of Ni may be continuously decreased from the central portion to the surface or in the concentration gradient region. For example, a concentration of Ni may be decreased in a direction from the central portion to the surface within a range between about 0.95 and about 0.6.
- In an embodiment, when the first cathode active material particle includes manganese, a concentration of manganese may increase from the center to the surface or in the concentration gradient region. Thus, a content of manganese may increase at a region adjacent to the surface, so that defects such as an ignition and short-circuit caused by a penetration through the surface of the first cathode active material particle may be prevented or reduced, and a life-span of the lithium secondary electricity may be increased.
- In an embodiment, the content of manganese may be maintained substantially constant throughout an entire region of the first cathode active material particle.
- In an embodiment, when the first cathode active material includes cobalt, a concentration of cobalt may increase along a direction toward the surface in the concentration gradient region. In an embodiment, the content of cobalt may be maintained substantially constant throughout an entire region of the first cathode active material particle.
- In some embodiments, nickel, cobalt and manganese included in the first cathode active material particle may have a substantially constant concentration from the center to the surface, and the first cathode active material particle is not necessarily limited to a particle having the above-described concentration gradient region.
- In exemplary embodiments, the first cathode active material particle may have a multi-particle structure. The term “multi-particle” may refer to a secondary particle structure or a secondary particle shape formed by aggregation or assembly of a plurality of primary particles.
- The first cathode active material particle may be formed by a co-precipitation method of metal precursors. For example, a metal precursor solution may include precursors of metals that may be included in the cathode active material. For example, the metal precursors may include halides, hydroxides, acid salts, etc., of the metals.
- For example, the metal precursors may include a lithium precursor (e.g., lithium oxide, lithium hydroxide, etc.), a nickel precursor, a manganese precursor and a cobalt precursor.
- In some embodiments, the first cathode active material particle may be prepared by a solid phase mixing/reaction, and a method of preparing the first cathode active material particle is not be limited to the solution-based process.
- The first cathode active material particle may be mixed and stirred together with a binder, a conductive agent and/or a dispersive additive in a solvent to form a slurry. The slurry may be coated on the cathode
current collector 105, and dried and pressed to obtain the first cathodeactive material layer 112. - The binder may include an organic based binder such as a polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidenefluoride (PVDF), polyacrylonitrile, polymethylmethacrylate, etc., or an aqueous based binder such as styrene-butadiene rubber (SBR) that may be used with a thickener such as carboxymethyl cellulose (CMC).
- For example, a PVDF-based binder may be used as a cathode binder. In this case, an amount of the binder for forming the first cathode
active material layer 112, and an amount of the first cathode active material particles may be relatively increased. Thus, capacity and power output of the lithium secondary battery may be further improved. - For example, a PVDF-based binder may be used as a cathode binder. In this case, an amount of the binder for forming the first cathode
active material layer 112, and an amount of the first cathode active material particles may be relatively increased. Thus, capacity and power of the lithium secondary battery may be further improved. - The conductive agent may be added to facilitate electron mobility between the active material particles. For example, the conductive agent may include a carbon-based material such as graphite, carbon black, graphene, carbon nanotube, etc., and/or a metal-based material such as tin, tin oxide, titanium oxide, a perovskite material such as LaSrCoO3 or LaSrMnO3, etc.
- The second cathode
active material layer 114 may be formed on the first cathodeactive material layer 112. As illustrated inFIG. 1 , the second cathodeactive material layer 114 may be directly formed on an upper surface of the first cathodeactive material layer 112, and may serve as a coating layer of thecathode 100. - The second cathode
active material layer 114 may include a second cathode active material particle. The second cathode active material particle may include a lithium metal oxide containing nickel, cobalt and other transition metals. - In exemplary embodiments, a content (or molar ratio) of cobalt in the second cathode active material particle may be 15% or less. In this case, improved conductivity and low resistance may be achieved while realizing high power/capacity of the lithium secondary battery.
- In exemplary embodiments, the second cathode active material particle may have a single particle shape or a single particle structure. The term “single particle shape” herein may be used to exclude a secondary particle structure in which a plurality of primary particles mat be agglomerated or combined with each other.
- In some embodiments, the second cathode active material particle may have a structure in which a plurality of primary particles are integrally merged to be converted into a substantially single particle. In an embodiment, the single particle shape may include a monolithic shape in which several (e.g., 2 to 10) independent particles are adjacent or attached to each other.
- In exemplary embodiments, the second cathode active material particle may have a substantially constant or fixed concentration throughout an entire region of the particle. For example, concentrations of metals except for lithium may be substantially uniform or constant from a central portion of the particle to a surface of the particle in the second cathode active material particle.
- In some embodiments, the second cathode active material particle may include nickel (Ni), cobalt (Co) and manganese (Mn). As described above, concentrations or molar ratios of Ni, Co and Mn may be substantially uniform or constant throughout the entire region of the second cathode active material particle.
- A concentration of nickel in the second cathode active material particle may be less than a concentration of nickel in the first cathode active material particle. For example, the concentration of nickel in the second cathode active material particle may be fixed to be less than the concentration of nickel at the surface of the first cathode active material particle.
- In some embodiments, a molar ratio of Ni among metals except for lithium in the second cathode active material particle may be 50% or more, preferably 60% or more. Within this range, sufficient thermal and penetration stability may be obtained from the second cathode
active material layer 114 without degrading capacity/power output of thecathode 100. - In some embodiments, the second cathode active material particle may include a lithium metal oxide represented by the following
Chemical Formula 2. -
LixNiaCobMncM4dM5eOy [Chemical Formula 2] - In the
Chemical Formula 2 above, M4 may include at least one element selected from Ti, Zr, Al, Mg, Si, B or Cr. M5 may include at least one element selected from Sr, Y, W or Mo. InChemical Formula - As represented by
Chemical Formula 2, an amount of Ni may be largest of those of the metals except for lithium in the second cathode active material particle in consideration of capacity and stability of the lithium secondary battery. For example, the concentrations may be decreased in a sequential order of Ni, Mn and Co. In a preferable embodiment, the concentration ratio of Ni:Co:Mn in the second cathode active material particle may be substantially about 65:15:20. - In some embodiments, the second cathode active material particle may be prepared by a solid-state thermal treatment of the metal precursors. For example, a lithium precursor, the nickel precursor, the manganese precursor and the cobalt precursor may be mixed according to the composition of the
Chemical Formula 2 above to form a precursor powder. - The precursor powder may be thermally treated in a furnace at, e.g., a temperature from about 700° C. to about 1200° C., and the precursors may be merged or fused into a substantially single particle shape to obtain the second cathode active material particle having a single particle shape. The thermal treatment may be performed under an air atmosphere or an oxygen atmosphere so that the second cathode active material particle may be formed as a lithium metal oxide particle.
- Within the above temperature range, generation of secondary particles may be substantially suppressed, and the second cathode active material particle without defects therein may be achieved. Preferably, the thermal treatment may be performed at a temperature from about 800° C. to about 1,000° C.
- The second cathode active material may be mixed and stirred together with a binder, a conductive agent and/or a dispersive additive in a solvent to form a slurry. The slurry may be coated on the first cathode
active material layer 112, and dried and pressed to obtain the second cathodeactive material layer 114. The binder and the conductive agent substantially the same as or similar to those used in the first cathodeactive material layer 112 may be also used. - In exemplary embodiments, a weight ratio of the second cathode active material particle and the first cathode active material particle included in the cathode
active material layer 110 may be from 1:9 to 6:4. The weight ratio of the first cathode active material particles and the second cathode active material particles having different compositions or molar ratios from each other may be controlled to implement enhanced mechanical property and high energy while using the multi-layered structure. - In exemplary embodiments, the first cathode
active material layer 112 contacting the cathodecurrent collector 105 may include the lithium metal oxide having a higher nickel amount than that of the second cathode active material particle in the second cathodeactive material layer 114. Thus, high capacity/power may be effectively achieved from a current through the cathodecurrent collector 105. - The second cathode
active material layer 114 that may be exposed at an outer surface of thecathode 100 may include the second cathode active material particle having a relatively reduced nickel amount so that thermal stability and life-span stability may be enhanced. - As described above, the second cathode
active material layer 114 may include the second cathode active material particle having a structure of the single particle shape to suppress generation of cracks during a pressing process. Thus, the second cathodeactive material layer 114 may substantially serve as a cathode coating layer improving the mechanical property. - In exemplary embodiments, an average diameter of the second cathode active material particle (D50) may be in a range from 3 μm to 6 μm, and a particle size distribution of the second cathode active material particles may satisfy
Equation 1 below. -
1≤D 90 /D 10≤4 [Equation 1] - In
Equation 1, D90 and D10 represent particle size values corresponding to 90% and 10%, respectively, with respect to a maximum particle size in a volume-based cumulative particle size distribution. - In this case, a particle deformation in the second positive electrode active material layer may be suppressed to achieve the lithium secondary battery having a high energy density while implementing a long-term storage property.
- In some embodiments, a diameter (e.g., D50) of the second cathode active material particle may be smaller than that of the first cathode active material particle. Accordingly, a packing property in the second cathode
active material layer 114 may be increased, and propagation of heat or crack when being penetrated or pressed may be more effectively suppressed or reduced. - In exemplary embodiments, the second cathode active material particle may have a crystallite size from 200 nm to 600 nm. The crystallite size may be measured based on a 104 peak according to an X-ray diffraction pattern analysis (XRD analysis). For example, the crystallite size may be estimated using a peak broadening of XRD data, and the crystallite size may be quantitatively calculated using a Scherrer equation.
- In some embodiments, the first cathode active material particle and/or the second cathode active material particle may further include a coating layer on a surface thereof. For example, the coating layer may include Al, Ti, Ba, Zr, Si, B, Mg, P, W, an alloy thereof or on oxide thereof. These may be used alone or in a combination thereof. The first cathode active material particle may be passivated by the coating layer so that penetration stability and life-span of the battery may be further improved.
- In an embodiment, the elements, the alloy or the oxide of the coating layer may be inserted in the cathode active material particle as dopants.
- In some embodiments, a thickness of the second cathode
active material layer 114 may be less than that of the first cathodeactive material layer 112. Accordingly, the second cathodeactive material layer 114 may serve as a coating layer providing a penetration barrier, and the first cathodeactive material layer 112 may serve as an active layer providing power/capacity. - For example, the thickness of the first cathode
active material layer 112 may be in a range from about 50 μm to about 200 μm. The thickness of the second cathodeactive material layer 114 may be in a range from about 10 μm to about 100 μm. -
FIGS. 2 and 3 are a top planar view and a cross-sectional view, respectively, schematically illustrating a lithium secondary battery in accordance with exemplary embodiments. Specifically,FIG. 3 is a cross-sectional view taken along a line I-I′ ofFIG. 2 in a thickness direction of the lithium secondary battery. - Referring to
FIGS. 2 and 3 , a lithiumsecondary battery 200 may include anelectrode assembly 150 housed in acase 160. Theelectrode assembly 150 may include thecathode 100, an anode 130 and a separation layer 140 repeatedly stacked as illustrated inFIG. 3 . - The
cathode 100 may include the cathodeactive material layer 110 coated on the cathodecurrent collector 105. Although not illustrated in detail inFIG. 3 , the cathodeactive material layer 110 may include a multi-layered structure including the first cathodeactive material layer 112 and the second cathodeactive material layer 114 as described with reference toFIG. 1 . - The anode 130 may include an anode current collector 125 and an anode active material layer 120 formed by coating an anode active material on the anode current collector 125. The anode active material commonly used in the related art may be used without a specific limitation.
- The separation layer 140 may be interposed between the
cathode 100 and the anode 130. The separation layer 140 may include a porous polymer film prepared from, e.g., a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene/butene copolymer, an ethylene/hexene copolymer, an ethylene/methacrylate copolymer, or the like. The separation layer 140 may be also formed from a non-woven fabric including a glass fiber with a high melting point, a polyethylene terephthalate fiber, or the like. - In some embodiments, an area and/or a volume of the anode 130 (e.g., a contact area with the separation layer 140) may be greater than that of the
cathode 100. Thus, lithium ions generated from thecathode 100 may be easily transferred to the anode 130 without loss by, e.g., precipitation or sedimentation. Therefore, the enhancement of power and stability by the combination of the first and second cathode active material layers 112 and 114 may be effectively implemented. - In exemplary embodiments, an electrode cell may be defined by the
cathode 100, the anode 130 and the separation layer 140, and a plurality of the electrode cells may be stacked to form anelectrode assembly 150 having, e.g., a jelly roll shape. For example, theelectrode assembly 150 may be formed by winding, laminating or folding of the separation layer 140. - The
electrode assembly 150 may be accommodated in anouter case 160 together with an electrolyte to form the lithium secondary battery. In exemplary embodiments, the electrolyte may include a non-aqueous electrolyte solution. - The non-aqueous electrolyte solution may include a lithium salt and an organic solvent. The lithium salt may be represented by Li+X−, and an anion of the lithium salt X− may include, e.g., F−, Cl−, Br−, I−, NO3 −, N(CN)2 −, BF4 −, ClO4 −, PF6 −, (CF3)2PF4 −, (CF3)3PF3 −, (CF3)4PF2 −, (CF3)5PF−, (CF3)6P−, CF3SO3 −, CF3CF2SO3 −, (CF3SO2)2N−, (FSO2)2N−, CF3CF2(CF3)2CO−, (CF3SO2)2CH−, (SF5)3C−, (CF3SO2)3C−, CF3(CF2)7SO3 −, CF3CO2 −, CH3CO2 −, SCN−, (CF3CF2SO2)2N−, etc.
- The organic solvent may include propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), methylpropyl carbonate, dipropyl carbonate, dimethyl sulfoxide, acetonitrile, dimethoxy ethane, diethoxy ethane, vinylene carbonate, sulfolane, gamma-butyrolactone, propylene sulfite, tetrahydrofuran, etc. These may be used alone or in a combination thereof.
- As illustrated in
FIG. 2 , an electrode tab (a cathode tab and an anode tab) may be formed from each of the cathodecurrent collector 105 and the anode current collector 125 to extend to one end of thecase 160. The electrode tabs may be welded together with the one end of thecase 160 to form an electrode lead (acathode lead 107 and an anode lead 127) exposed at an outside of thecase 160. -
FIG. 2 illustrates that thecathode lead 107 and theanode lead 127 protrude from an upper side of thecase 160 in a planar view. However, positions of the electrode leads are not specifically limited. For example, the electrode leads may protrude from at least one of lateral sides of thecase 160, or may protrude from a lower side of thecase 160. Further, thecathode lead 107 and theanode lead 127 may protrude from different sides of thecase 160. - The lithium secondary battery may be fabricated into a cylindrical shape using a can, a prismatic shape, a pouch shape, a coin shape, etc.
- Hereinafter, preferred embodiments are proposed to more concretely describe the present invention. However, the following examples are only given for illustrating the present invention and those skilled in the related art will obviously understand that various alterations and modifications are possible within the scope and spirit of the present invention. Such alterations and modifications are duly included in the appended claims.
- A first cathode active material particle having a secondary particle structure and a composition of LiNi0.80Co0.12Mn0.08O2 was prepared. A first cathode mixture was prepared by mixing the first cathode active material particle, Denka Black as a conductive agent and PVDF as a binder in a mass ratio of 92:5:3, respectively.
- A second cathode active material particle having a composition of LiNi0.65Co0.15Mn0.20O2 having a single particle shape was prepared (D90=6.5 μm, D10=3.5 μm). A second cathode mixture was prepared by mixing the second cathode active material particle, Denka Black as a conductive agent and PVDF as a binder in a mass ratio of 92:5:3, respectively.
- A mass ratio of the first cathode active material particle relative to the second cathode active material particle included in the first cathode mixture and the second cathode mixture was 8:2.
- The first cathode mixture was coated on an aluminum current collector, and the second cathode mixture was coated thereon, and then dried and pressed to form a cathode. An electrode density of the cathode was 3.7 g/cc.
- An anode slurry was prepared by mixing 93 wt % of a natural graphite as an anode active material, 5 wt % of a flake type conductive agent KS6, 1 wt % of SBR as a binder, and 1 wt % of CMC as a thickener. The anode slurry was coated, dried and pressed on a copper substrate to form an anode.
- The cathode and the anode obtained as described above were notched with a proper size and stacked, and a separator (polyethylene, thickness: 25 μm) was interposed between the cathode and the anode to form an electrode cell. Each tab portion of the cathode and the anode was welded. The welded cathode/separator/anode assembly was inserted in a pouch, and three sides of the pouch (e.g., except for an electrolyte injection side) were sealed. The tab portions were also included in sealed portions. An electrolyte was injected through the electrolyte injection side, and then the electrolyte injection side was also sealed. Subsequently, the above structure was impregnated for more than 12 hours.
- The electrolyte was prepared by dissolving 1M LiPF6 in a mixed solvent of EC/EMC/DEC (25/45/30; volume ratio), and then 1 wt % of vinylene carbonate, 0.5 wt % of 1,3-propensultone (PRS), and 0.5 wt % of lithium bis(oxalato) borate (LiBOB) were added.
- Thereafter, pre-charging was performed for 36 minutes at a current (5 A) corresponding to 0.25 C. After 1 hour, degassing was performed, and charge and discharge for aging were performed (charging condition CC-CV 0.2 C 4.2V 0.05 C CUT-OFF, discharging condition CC 0.2 C 2.5V CUT-OFF) after more than 24 hours. Subsequently, standard charging and discharging was performed (charging condition CC-CV 0.5 C 4.2V 0.05 C CUT-OFF, discharging condition CC 0.5 C 2.5V CUT-OFF).
- A lithium secondary battery was fabricated by the same method as that in Example 1, except that a particle having a single particle shape and a composition of LiNi0.65Co0.15Mn0.20O2 (D90=9.5 μm, D10=2.5 μm) was used as the second cathode active material particle.
- A lithium secondary battery was fabricated by the same method as that in Example 1, except that the first cathode active material particle and the second cathode active material particle were mixed to form a single cathode mixture, and then a cathode active material layer was formed as a single layer.
- A lithium secondary battery was fabricated by the same method as that in Example 1, except that a particle having a secondary particle structure and a composition of LiNi0.65Co0.15Mn0.20O2 was used as the second cathode active material particle.
- A lithium secondary battery was fabricated by the same method as that in Example 1, except that the secondary particle of Comparative Example 2 was used as the second cathode active material particle, and the first cathode active material particle and the second cathode active material particle were mixed to form a single cathode mixture, and then a cathode active material layer was formed as a single layer.
- A lithium secondary battery was fabricated by the same method as that in Example 1, except that a particle having a single particle shape and a composition of LiNi0.65Co0.15Mn0.20O2 (D90=13.5 μm, D10=2.8 μm) was used as the second cathode active material particle.
- A lithium secondary battery was fabricated by the same method as that in Example 1, except that LiNi1/3Co1/3Mn1/3O2 (single particle shape NCM111) having a single particle shape was used as the second cathode active material particle.
- (1) Evaluation on Life-Span Property at High Temperature
- 500 cycles of a charging (CC-CV 1.0 C 4.2V 0.05 C CUT-OFF) and a discharging (CC 1.0 C 2.5V CUT-OFF) were repeated in a chamber at 45° C. using the secondary batteries of Examples and Comparative Examples. Life-span properties at high temperature were measured by a percentage (%) of a remaining capacity and a DC-IR at 500th cycle relative to those at 1st cycle. Further, BET (Brunauer-Emmett-Teller) increasing rates after the pressing process of the cathodes in Examples and Comparative Examples were measured. The results are shown in Table 1 below.
- (2) Evaluation on High Temperature Storage Property
- After charging (CC-CV 0.5 C 4.2V 0.05 C CUT-OFF) the secondary batteries of Examples and Comparative Examples and storing in a chamber of 60° C. for 8 weeks, remaining capacities and DC-IR increasing rates were measured
- Further, after storing the secondary batteries for 8 weeks, amounts of generated gas were measured using a gas capture analysis. The results are shown in
FIG. 4 . -
TABLE1 1DC-IR D90/D10 BET DC-IR Remaining increasing (Second increasing Remaining increasing Capacity rate cathode rate after Capacity rate (%) (%) Cathode active pressing (%) (%) (after 8 (after 8 Structure material) (%) (500 cycle) (500 cycle) weeks) weeks) Example 1 Double 1.9 119 82.2 152 85.7 125 Layer Example 2 Double 3.8 129 80.1 172 81.1 132 Layer Comparative Single 1.9 125 80.5 170 82.4 130 Example Layer 1 Comparative Double 2.9 178 69.8 205 70.2 142 Example Layer 2 Comparative Single 2.9 185 65.2 223 69.1 145 Example Layer 3 Comparative Double 4.8 155 72.9 211 71.4 141 Example Layer 4 Comparative Double 4.3 150 75.3 195 73.2 138 Example Layer 5 - Referring to Table 1 and
FIG. 4 , in Examples where the first cathode active material layer containing the secondary particle NCM and the second cathode active material layer containing the single particle NCM were formed in a double-layered structure, improved life-span properties and capacity retentions under harsh conditions at high temperature were achieved compared to those from Comparative Examples. - Further, the secondary battery of Comparative Example 5 having different metal ratio of the second cathode active material particle provided life-span and storage properties at high temperature less than those of Examples.
Claims (15)
1≤D 90 /D 10≤4 [Equation 1]
LixNiaM1bM2cOy [Chemical Formula 1]
0<x≤1.2, 2≤y≤2.02, 0.6≤a≤0.95, and 0.05≤b+c≤0.4.
LixNiaCobMncM4dM5eOy [Chemical Formula 2]
0<x<1.5, 2≤y≤2.02, 0.5≤a≤0.75, 0.05≤b≤0.15, 0.20≤c≤0.30, 0≤d≤0.03, 0≤e≤0.03 and 0.98≤a+b+c≤1.03.
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Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008147068A (en) * | 2006-12-12 | 2008-06-26 | Ise Chemicals Corp | Lithium composite oxide for nonaqueous electrolyte secondary battery |
KR20090082790A (en) * | 2008-01-28 | 2009-07-31 | 주식회사 에너세라믹 | Composite cathode active material for lithium secondary battery, methode of preparing thereof, and lithium secondary battery comprising the same |
US7763386B2 (en) * | 2002-01-08 | 2010-07-27 | Sony Corporation | Cathode active material and non-aqueous electrolyte secondary cell using same |
JP2012085530A (en) * | 2012-01-16 | 2012-04-26 | Toshiba Corp | Semiconductor device and dc-dc converter |
US20130202966A1 (en) * | 2010-01-14 | 2013-08-08 | Ecopro Co., Ltd. | Method for preparing positive electrode active material precursor and positive electrode material for lithium secondary battery having concentration-gradient layer using batch reactor, and positive electrode active material precursor and positive electrode material for lithium secondary battery prepared by the method |
US20170092935A1 (en) * | 2011-01-05 | 2017-03-30 | Iucf-Hyu (Industry-University Cooperation Foundation Hanyang University) | Positive electrode active material and secondary battery comprising the same |
US20170155139A1 (en) * | 2014-07-07 | 2017-06-01 | Hitachi Metals, Ltd. | Lithium ion secondary battery cathode material, lithium ion secondary battery cathode and lithium ion secondary battery that use same, and method for manufacturing lithium ion secondary battery cathode material |
US20170288221A1 (en) * | 2016-03-31 | 2017-10-05 | Nichia Corporation | Method of producing positive electrode active material for nonaqueous electrolyte secondary battery |
US10153485B2 (en) * | 2003-04-11 | 2018-12-11 | Murata Manufacturing Co., Ltd. | Positive electrode active material and non-aqueous electrolyte secondary battery containing the same |
US11646404B2 (en) * | 2018-10-18 | 2023-05-09 | Sk On Co., Ltd. | Lithium secondary battery |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2017135792A1 (en) | 2016-02-04 | 2017-08-10 | 주식회사 엘지화학 | Positive electrode and lithium secondary battery comprising same |
KR102359103B1 (en) * | 2018-02-01 | 2022-02-08 | 주식회사 엘지에너지솔루션 | Positive electrode active material for secondary battery, method for preparing the same and lithium secondary battery comprising the same |
-
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-
2021
- 2021-07-08 EP EP21184615.9A patent/EP3944366A1/en active Pending
- 2021-07-15 US US17/377,024 patent/US20220020984A1/en active Pending
- 2021-07-19 CN CN202110811949.XA patent/CN113964299A/en active Pending
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7763386B2 (en) * | 2002-01-08 | 2010-07-27 | Sony Corporation | Cathode active material and non-aqueous electrolyte secondary cell using same |
US10153485B2 (en) * | 2003-04-11 | 2018-12-11 | Murata Manufacturing Co., Ltd. | Positive electrode active material and non-aqueous electrolyte secondary battery containing the same |
JP2008147068A (en) * | 2006-12-12 | 2008-06-26 | Ise Chemicals Corp | Lithium composite oxide for nonaqueous electrolyte secondary battery |
KR20090082790A (en) * | 2008-01-28 | 2009-07-31 | 주식회사 에너세라믹 | Composite cathode active material for lithium secondary battery, methode of preparing thereof, and lithium secondary battery comprising the same |
US20130202966A1 (en) * | 2010-01-14 | 2013-08-08 | Ecopro Co., Ltd. | Method for preparing positive electrode active material precursor and positive electrode material for lithium secondary battery having concentration-gradient layer using batch reactor, and positive electrode active material precursor and positive electrode material for lithium secondary battery prepared by the method |
US20170092935A1 (en) * | 2011-01-05 | 2017-03-30 | Iucf-Hyu (Industry-University Cooperation Foundation Hanyang University) | Positive electrode active material and secondary battery comprising the same |
JP2012085530A (en) * | 2012-01-16 | 2012-04-26 | Toshiba Corp | Semiconductor device and dc-dc converter |
US20170155139A1 (en) * | 2014-07-07 | 2017-06-01 | Hitachi Metals, Ltd. | Lithium ion secondary battery cathode material, lithium ion secondary battery cathode and lithium ion secondary battery that use same, and method for manufacturing lithium ion secondary battery cathode material |
US20170288221A1 (en) * | 2016-03-31 | 2017-10-05 | Nichia Corporation | Method of producing positive electrode active material for nonaqueous electrolyte secondary battery |
US11646404B2 (en) * | 2018-10-18 | 2023-05-09 | Sk On Co., Ltd. | Lithium secondary battery |
Non-Patent Citations (3)
Title |
---|
modified english translation JP2008147068A- as taught by Abe et al (Year: 2008) * |
modified english translation JP2012085530, as taught by Endo et al. (Year: 2012) * |
modified english translation KR20090082790A as taught by Sun et al. (Year: 2009) * |
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